Fluid projection apparatus for cleaning heat exchangers

ABSTRACT

A combined soot blower and liquid projector for cleaning boiler surfaces has a main lance tube telescopically overfitted on a feed tube and carrying a nozzle assembly at its outer end for projecting steam and/or air supplied through said tubes, a second pair of telescoped tubes inside and substantially smaller in diameter than the two tubes first mentioned and including a slidable liquid lance having a jet member connected to the nozzle assembly to discharge liquid at right angles to the stream or air. During projection of liquid, steam and/or air is supplied to the outer tubes to cool them and the nozzle assembly.

United States Patent Locke, Sr. et al. [45] May 23, 1972 [54] FLUIDPROJECTION APPARATUS FOR 2,958,311 11/1960 Singleton 122/392 CLE G HEATEXC G FOREIGN PATENTS OR APPLICATIONS [72] Inventors: James W. Locke,Sr.; John C. Goeller Ill,

both of Lancaster, Ohio 669,895 1/1966 Belgmm ..l5/317 [73] Assignee:Diamond Power Specialty Corporation, Primary Examiner-Kenneth SpragueLancaster, Ohio Attorneyl-Iamess, Dickey & Pierce [21] Appl 139383 Acombined soot blower and liquid projector for cleaning boiler surfaceshas a main lance tube telescopically overfitted Related Apphcauon Dam ona feed tube and carrying a nozzle assembly at its outer end [63]Continuation of Ser. No. 16,291, Mar. 4, 1970, abanfor projecting steamand/or air supplied through said tubes, a cloned. second pair oftelescoped tubes inside and substantially smaller in diameter than thetwo tubes first mentioned and in- [52] US. Cl ..122/379, 122/390 Cludinga slidable liquid lance having a jet member connected [5 1 Int. Cl..F22b 37/48 to the nozzle assembly to discharge liquid at right anglesto the [58] Field of Search ..l22/379, 390, 391, 392; stream or a r. Durng projection of l qu d, stea and/0 air is 16/316, 317, 318 supplied tothe outer tubes to cool them and the nozzle assembly.

[56] References Cited 6 Claims, 5 Drawing Figures UNITED STATES PATENTS1,809,221 6/1931 Snow et a1. ..l22/392 FLUID PROJECTION APPARATUS FORCLEANING HEAT EXCHANGERS This application is a continuation ofapplication Ser. No. 1 6,291, filed Mar. 4, 1970, now abandoned.

BACKGROUND OF THE INVENTION In the art of cleaning the heat exchangingsurfaces of boilers and the like by projecting fluids thereagainstthroughsoot blowers and similar apparatus, preferred practice involvesthe use of air or steam as the blowing medium (although a mixture ofthese has sometimes been used). It has long been recognized that wheredifficult cleaning conditions exist, as where heavy slagging occurs, theprojection of water or an aqueous solution in lieu of or in conjunctionwith steam and/or air provides increased cleaning efiiciency. The tradeavoids the use of water or aqueous solutions, except where cleaning isnot otherwise possible, however, because of certain disadvantages,including the undesirable cooling effect and the necessity for carefulcontrol to avoid undue thermal shock.

The general object of the present invention may be characterized as toprovide an improved apparatus and method whereby both a liquid cleaningagent and gaseous and/or vapor cleaning agents may be efficientlyprojected against the heat exchanging surfaces. It is also an object ofthe invention to provide improved apparatus of the indicated characterwhich is compatible with and readily interchangeable with standardizedcommercial types of soot blowers and which in its constructionincorporates many components identical with those employed in theconstruction of such soot blowers, the apparatus of the presentinvention being adapted to be substituted for or added to regular orexisting soot blowers, as this may be advisable, for example, wherefouling is severe or where a change of fuel or other changed conditionscreates heavy slagging and difficult cleaning conditions.

Other objects and advantages will become apparent upon consideration ofthe present disclosure in its entirety.

BRIEF DESCRIPTION OF THE FIGURES OF DRAWING FIG. I is a side elevationalview partly broken away and partly in section showing a dual fluidprojector constructed in accordance with the present invention;

FIGS. 2 and 3 are detailed sectional elevational views on a larger scaleof fragmentary portions of the apparatus corresponding to the parts inthe areas designated by the circles II and III respectively of FIG. 1;

FIG. 4 is a detailed longitudinal sectional view of the nozzle assemblyand adjacent parts, also on a larger scale and partly in elevation,taken substantially as indicated by the line and arrows IVIV of FIG. 1and looking in the direction of the arrows; and

FIG. 5 is a fragmentary sectional view of the rear portion of a nozzlebody generally similar to that shown in FIG. 4 but showing a modifieddouble-nozzle liquid discharge construction.

DETAILED DESCRIPTION OF PREFERRED FORMS OF THE INVENTION Referring nowto the drawing, reference character designates the main supporting beamof the device, the beam and the principle driving components being shownas corresponding to those employed in a well-known type of longretracting IK soot blower. Such components will require no detaileddescription. They include a main or outer lance tube portion 12projectable through a wall box 14, toward the right in FIG. 1, into aboiler (not shown) and retractable therefrom to the withdrawn positionshown. The outer lance tube portion I2 corresponds to a conventionallance tube, being rotatable as well as longitudinally movable by meansincluding the carriage I5 and motor 16, and is slidably overfitted upona stationary feed tube 18 which projects thereinto from the rear tosupply blowing medium thereto. As shown in FIG. 2, the feed tube 18 isconnected to a fitting 20 carried at the rear end of the assembly havinga straight through passage 22 therein through which the principalblowing medium such as steam and/or air may be supplied from a suitablesupply system (not shown) which conventionally may comprise a source ofsteam or air and a main blowing medium control valve (not shown) as iswell known in the art.

The fitting 20 also includes a side opening 24 which is connected to aliquid supply pipe 25 which may be a source of water under pressuredelivered thereto, the pipe being welded to a side nipple portion 26,but the interior of the water pipe being connected to a conduit 28 whichis bent at right angles to communicate only with a stationary liquidfeed tube 30 concentrically supported in and of substantially smallerdiameter than the feed tube 18, and projecting forwardly therein Thecomplete lance assembly, which is generally designated 11, includes, inaddition to the outer tube 12, an inner liquid conducting lance tubeportion 33 which travels and rotates with the main lance tube portion 12and is slidably overfitted on the liquid feed tube 30, and remainsinterengaged therewith at all times to conduct liquid from the feed tube30 to a nozzle assembly comprising a nozzle body generally designated 35attached to outer end of the lance tube assembly. The liquid lance tube33 is spacedly axially supported in the main blowing medium feed tube 18by radial spacing fins 32 which interpose no substantial resistance tofree flow of blowing medium through the main feed tube 18. The liquidfeed tube 30 is in turn supported by the liquid lance tube.

The interior of the outer shell 37 of the nozzle body 35 communicateswith the main lance tube 12 and contains a pair of diametrically opposednozzle elements 36 for discharging the gaseous or vapor cleaning agentagainst the heat exchanging surfaces as the lance travels and rotateswithin the blower. The arrangement and operation of the aforementionednozzle portions may conform to conventional soot blower practice.

At its forward end the traveling liquid supply lance tube portion 33 isconnected by means of an elbow 38 to a water nozzle 40 which dischargesthrough an opening 42 in the side wall of the nozzle body, the waternozzle being surrounded and shielded by the tube 44 whichis welded tothe nozzle body 35 and to the elbow to support the latter and the waternozzle. The water nozzle discharges perpendicularly to both of the mainnozzle elements 36 so that the blast patterns are not disturbed if bothtypes of media are used simultaneously.

Under severe slagging or other difficult cleaning conditions, water or asuitable aqueous solution may be discharged through the liquid nozzle 40either with or prior to the main blowing medium discharge through thenozzle elements 36. The preferred method includes a preliminarydischarge of liquid sufficient to wet the heavily encrusted surfaces foran instant and create a cooling effect to shrink and crack the crust,whereafter the full volume discharge of steam and/or air completes thecleaning operation. Throughout the period in which the lance isprojected, however, including the period of the initial liquiddischarge, a reduced amount of the steam and/or air is supplied throughouter tube 12 of the lance and the outer shell 37 of the nozzle body, ata relatively low pressure compared to the full blowing pressure, to coolthese parts and prevent them from being overheated and damaged. This isdesirable because of the fact that the presence of the liquid in theinner pair of tubes 30, 33 cannot protect the outer portions of thelance and nozzle body in high temperature regions, on account of thehigh insulating effect that would exist in the spaces between tubes 12,18, 33 and in the nozzle body shell 37, if these spaces were empty.

In the modified nozzle construction shown in FIG. 5, two liquiddischarge nozzles 40 are provided, both lying in a plane perpendicularto the nozzle means 36' for the main blowing medium although inclined tothe axis so as to sweep displaced helices, as shown.

This Detailed Description of Preferred Forms of the Invention, and theaccompanying drawings, have been fumished in compliance with thestatutory requirement to set forth the best mode contemplated by theinventors of carrying out the invention. The prior portions consistingof the Abstract of the Disclosure and the Background of the Inventionare furnished without prejudice to comply with administrativerequirements of the Patent Office.

What is claimed is:

1. Means for discharging liquid and a gas or vapor into a hightemperature zone of a furnace or the like comprising in combination witha support, a lance tube supported thereby for rotation and longitudinaltravel so as to move a forward end thereof into and out of such a zone,a hollow nozzle body carried by the forward end of the lance tube andhaving a lateral discharge orifice therein, and means for feeding a gasor vapor through the lance tube and out through said orifice,characterized by a pair of telescopably interfitted tubes within andsubstantially smaller in diameter than the lance tube and comprising aliquid feed tube fixed with respect to the support, a liquid lance tubeslidably interfitted with the liquid feed tube and projecting forwardlytherefrom within the first-mentioned lance tube and connected thereto atits forward end to move therewith, said liquid feed tube and liquidlance tube being isolated from the interior of the first-mentioned lancetube, the liquid lance tube having a liquid discharge orifice openinglaterally outwardly through and to the outside of the nozzle assembly atan angle displaced sufficiently from the first-mentioned dischargeorifice so that the blast patterns from said two orifices do not disturbone another when operating simultaneously.

2. Means as defined in claim 1 wherein said two discharge orifices aresubstantially at right angles to each other.

3. The method of operating a dual discharge projection-type tubularcleaning device for furnaces and the like which device is adapted to beprojected into and retracted from a hot zone, and which has radiallyspaced isolated passages including an outer passage for gas or vapor andan inner passage for liquid, comprising conducting liquid through theinner passage and discharging it therefrom into such a hot zone whilesimultaneously conducting gas or vapor through the outer passage at arelatively low flow rate and discharging it in a different directioninto such zone, and thereafter increasing the pressure of discharge ofthe gas or vapor.

4. Means as defined in claim 1 wherein said orifices discharge inlongitudinal axial planes which are perpendicular to each other.

5. Means as defined in claim 4 including at least two liquid dischargeorifices directed in opposite directions in a common plane perpendicularto the discharge plane of the first-mentioned orifice.

6. Means as defined in claim 4 including at least two liquid dischargeorifices directed in opposite directions in a common plane perpendicularto the discharge plane of the first-mentioned orifice, but inclined tothe longitudinal axis.

1. Means for discharging liquid and a gas or vapor into a hightemperature zone of a furnace or the like comprising in combination witha support, a lance tube supported thereby for rotation and longitudinaltravel so as to move a forward end thereof into and out of such a zone,a hollow nozzle body carried by the forward end of the lance tube andhaving a lateral discharge orifice therein, and means for feeding a gasor vapor through the lance tube and out through said orifice,characterized by a pair of telescopably interfitted tubes within andsubstantially smaller in diameter than the lance tube and comprising aliquid feed tube fixed with respect to the support, a liquid lance tubeslidably interfitted with the liquid feed tube and projecting forwardlytherefrom within the firstmentioned lance tube and connected thereto atits forward end to move therewith, said liquid feed tube and liquidlance tube being isolated from the interior of the first-mentioned lancetube, the liquid lance tube having a liquid discharge orifice openinglaterally outwardly through and to the outside of the nozzle assembly atan angle displaced sufficiently from the firstmentioned dischargeorifice so that the blast patterns from said two orifices do not disturbone another when operating simultaneously.
 2. Means as defined in claim1 wherein said two discharge orifices are substantially at right anglesto each other.
 3. The method of operating a dual dischargeprojection-type tubular cleaning device for furnaces and the like whichdevice is adapted to be projected into and retracted from a hot zone,and which has radially spaced isolated passages including an outerpassage for gas or vapor and an inner passage for liquid, comprisingconducting liquid through the inner passage and discharging it therefrominto such a hot zone while simultaneously conducting gas or vaporthrough the outer passage at a relatively low flow rate and dischargingit in a different direction into such zone, and thereafter increasingthe pressure of discharge of the gas or vapor.
 4. Means as defined inclaim 1 wherein said orifices discharge in longitudinal axial planeswhich are perpendicular to each other.
 5. Means as defined in claim 4including at least two liquid discharge orifices directed in oppositedirections in a common plane perpendicular to the discharge plane of thefirst-mentioned orifice.
 6. MEans as defined in claim 4 including atleast two liquid discharge orifices directed in opposite directions in acommon plane perpendicular to the discharge plane of the first-mentionedorifice, but inclined to the longitudinal axis.